A Wireless Access Protocol (WAP) load balancer is a device that distributes WAP traffic received over a wireless network on an Internet Protocol (IP) bearer network among a group of WAP gateways. Each WAP gateway translates requests from the WML stack to a WWW protocol stack, such as HTML and TCP/IP. The WAP gateway encodes and decodes web content to reduce the size and number of packets traveling over the wireless network. The WAP gateway interfaces with subscriber databases in order to provide client specific services.
Because of the growth and size of the wireless subscriber market, content customers providing WAP services are quickly experiencing more bottlenecks at their WAP gateways. The WAP load balancer is used to distribute WAP traffic among WAP gateways in order to relieve and avoid bottlenecks in the system. With multiple WAP gateways, the WAP load balancer must ensure that all packets associated with a single session are sent to the same WAP gateway. A Wireless Session Protocol (WSP) is a session layer protocol for operation between a WAP client and a WAP gateway. The WSP allows for sessions to be suspended and resumed without the overhead of session tear-down and re-establishment. When a session is established, a session entry is set up in a database indexed by a session identifier. The suspend facility allows a wireless service provider to change the underlying network bearer resources. The session state is initially maintained using header information in the IP packets identifying source/destination IP addresses and/or source/destination port numbers. However, a subsequent resume request may arrive with a different IP source and port number. If this occurs, a query to a session state database will fail and the session will not be resumed at the previously chosen WAP gateway. Therefore, it is desirable to select a previously chosen WAP gateway in response to a suspend and resume operation.